1. Field of the Invention
This invention relates to new oligopeptide derivatives obtainable by reaction of alkyl and alkenyl succinic acid anhydrides with protein hydrolyzates.
2. Statement of the Related Art
It is known that the compatability of surfactants and surfactant-containing preparations with the skin can be significantly improved by addition of watersoluble proteins or protein degradation products. Protein degradation products have already been incorporated in surfactants, for example products have been used which are made by acylation of protein hydrolyzates with fatty acid chlorides or by condensation of fatty acid methylesters with protein hydrolyzates. Acylated oliogopeptides of this type are known as surfactants which are gentle to the skin, and are sold under the trademarks "Lamepon" and "Maypon."
Unfortunately, the prior art fatty acid-protein hydrolyzate condensates have disadvantages in terms of practical application, for example unsatisfactory washing and foaming power, high sensitivity of the foam to water hardness and to fats. In addition, the production of fatty acid-protein hydrolyzate condensates necessitates the use either of fatty acid chlorides or, in case of the fatty acid methylesters, of high-boiling solvents (for example ethylene glycol or dimethylsulfoxide) which are undesirable in the end product.